HI, I was wandering on how to get the Gannon Family Tesla Armor? I have started the For Auld Lang Syne quest and on the bit just before telling them who to side with.

Tell them to side with the NCR and tell Gannon not to fight at Hoover Dam.

but when I convice orion to fight for the ncr arcade runs up to me and talks a bit and then I have to talk to the remnants again to get my power armor and training when I leave I get completed quest and nothing else

Arcade should meet you when you leave the Remnants' Bunker.

I think my game is bugged he does not do that

Try waiting an hour right outside the bunker and are you sure you told hm not to rejoin the Remnant?

I dont really know